Multispeed transmission



y 9, 1950 s. w. BAKER 2,506,986

MULTISPEED TRANSMISSION Filed Jan. 9, 1946 4 Sheets-Sheet l IN V EN TOR.

ATTEIRNJIY ETANLEY VI. BAKER May 9, 1950 s. w. BAKER 2,506,986

MULTISPEED TRANSMISSION Filed Jan. 9, 1946 4 Sheets-Sheet 2 ATTEIRNEY y 1950 s. w. BAKER 2,506,986

MULTISPEED TRANSMISSION Filed Jan. 9, 1946 4Sheets-Sheet 3 INVEN TOR. STAN LEY W. BAKER.

ATTORNEY y 9, 1950 s. w. BAKER 2,506,986

MULTISPEED TRANSMISSION Filed Jan. 9, 1946 4 Sheets-Sheet 4 INVENTOR.

STANLEY W. BAKE R BY% I s ATT DRNEY mined by the input shaft and planet carrier independently of any lateral motion of the input and output shafts. Accordingly, it is possible to have relatively loose fits for the bearings of the sun gears and the internal gear 56 thereby permitting them to adjust themselves to equalize the load between the various planet pinions. As previously mentioned, the fixed internal gear 22 preferably may be provided with a conventional flexible support thereby helping to equalize the load on the pinions I6. illustrated in Patent No. 2,407,699. Also, the output shaft 54 preferably is made flexible by providing it with a relatively thin wall construction 54' whereby the sun gear 58 can follow any lateral motion of its associated planetary gear train independently of any lateral motion of the supercharger impeller (not shown) to which the shaft 54 is drivably connected.

The friction brake for the planet carrier 36, 38, 40, 42 comprises a plurality of annular frictionally engageable plates 62 and 64 alternately disposed and respectively splined to the rim of the carrier member 4.2 and to a drum 66 secured to the housing 26 by the bolts 24. An annular member 68 is also secured to the housing 26 by the bolts 24 and a piston '50 has seal rings I2 cooperating with the member 60 to provide a sealed annular chamber I relative to which the piston I6 is axially slidable.

' The friction brake for the internal gear 56 comprises a plurality of annular frictionally engageable plates 6 and I8 alternately disposed and respectively s lined to the rim of the gear 56 and to the drum 66. An annular member 80 is also secured to the housing 26 by the bolts 24 and a piston 82 has seal rings 84 cooperating with the member 8 to provide a sealed annular chamber 86 relative to which the piston 82 is axially slidable. A plate 88 is disposed between the set of frictionally engageable plates 62, 64 and the set of frictionally engageable plates 16, I6 and is held against axial movement along the drum 66 by a lock wire 90.

Fluid under pressure is adapted to be supplied to the annular chamber '14 or 86 from a conduit 92 under the control of a valve 94. In the position illustrated, fluid under pressure is supplied to the chamber I4 against the piston Ill via conduit 66 and passage 98 thereby frictionally clamping the plates 62 and 64 together to 'lock the pinion carrier 36, 38, 46, 42 against rotation. At the same time, the chamber 86 is in communication with a drain conduit I through passage Hi2 and conduit I04. When the valve 94 is moved to its dotted line position, fluid under pressure is admitted to the chamber 86 against piston 82 to lock the friction plates 16 and I8 together thereby preventing rotation of the internal gear 56. A pin I06 is disposed between the pistons and 82 to insure disengagement of either friction brake before the other is applied.

With this construction, when fluid pressure is supplied to the chamber I4 to clamp friction plates 62 and 64 together, the planet carrier '36, 38, 40, 42 is held stationary and the double planet pinions 32, 34 provide a step-up drive ratio from the intermediate shaft 28 to the output shaft 54. At the same time the friction plates 16 and I8 are disengaged and therefore the internal gear 56 is free to rotate. When the friction plates 16 and 18 are engaged and the friction plates 62 and 64 are disengaged, the planet carrier is freed for rotation but the internal gear 58 is now locked against rotation. The planet car- Such a flexible support is rier now rotates and the planet pinions 32, 34 provide a second, but smaller, step-up drive ratio from the intermediate shaft 28 to the output shaft 54. In the high speed ratio, the planet carrier 38 is held stationary so that there are no centrifugal forces on the planet pinion bearings while, in the low speed ratio, the planet carrier only rotates at approximately one and one half times the speed of the input shaft I0, whereby the centrifugal forces on the planet pinions are relatively low.

The modification of Figures 3 and 4 is quite similar to that of Figure 1 except an intermediate speed ratio has been added. In this modification, an input shaft IIO has an annular flange II2 having a plurality of studs H3 projecting therefrom and a plurality of planet pinions II4 are journaled about the studs I 43 and are held thereon by bolts H5. The planet pinions II4 are disposed in meshing engagement between a sun gear I I6 and an internal gear I I8. The internal gear H8 is rigidly secured to the housing I20 by studs I22 thereby providing a step-up drive from the input shaft H0 to the sun gear II6 similar to the initial step-up drive in Figure 1.

The sun gear I I6 is splined to an intermediate shaft I24 which is provided with a sun gear I26 meshing with a plurality of planet pinion gears I26. The pinion gears I28 are each formed integral with a larger pinion 530 and these double planet pinions are journaled in a carrier comprising end portions I62 and I34 and an intermediate portion I36 all clamped together by bolts I38. The carrier end portion 132 is piloted on a drum I40 secured to the housing I20 by bolts I42 and the carrier end portion I34 pilots the gear H6. The intermediate carrier portion I36 is piloted by the input shaft H0 and pilots the intermediate shaft I24 and an output shaft I44. The planet carrier I32, i34, I36 is similar to the corresponding planet carrier of Figure 1. An internal gear I46, piloted on the planet carrier, is disposed in meshing engagement with the smaller planet pinions I28 and an internal gear I48, also piloted on the planet carrier, is disposed in meshing engagement with the large planet pinion gears I30. The output shaft I44 has a sun gear I50 meshing with the large planet pinion gears I30.

The internal gear I46 is adapted to be clamped to the housing I20 by a friction brake. This friction brake comprises a plurality of annular frictionally engageable plates I52 and I54 alternately disposed and respectively splined to the rim of the gear I46 and to a drum I56 secured to the housing I20 by the studs I22. An annular member I58 is also secured to the housing I20 by the studs I 22 and a piston I60 has seal rings I62 cooperating with the annular member I56 to provide a sealed annular chamber I64 relative to which the piston I60 is slidable.

The planet carrier I32, I34, H6 is also adapted to be clamped to the housing I20 by a friction brake. This friction brake comprises a plurality of annular frictionally engageable plates I66 and I68 alternately disposed and respectively splined to the rim of the carrier portion I36 and to the rigid drum I56. An annular member H0 is also secured to the housing I20 by the studs I22 and the frictionally engageable plates I 52 and I54 and the frictionally engageable plates I66 and I68 is 5 held against axial movement relative to the drum I5S- by a'lock wire 98%. Also, a pluralityof circumferentially spaced-springs I82 extend through openings in a radial flange on the drum I56 to urge the pistons lIiIland I12 away from each other to their disengaged positions.

A valve #34 is provided for controlling'tlie application of fiuid pressure to the annular chambers I64 and lit. The valve H54 comprises a sleeve I86 anda plug I88 sl-idable therein. The plug I88 is provided with a central drain passage Isl), annular groove I92, and radial holes I94 and I96 communicating with the central passage: ISQ. In addition, the plug SE-is provided with a longitudinal groove ISB eXtendi-ng from the radial passage I95 and having a-length sufficient to straddle radial passages 2Ilil= and 292 the sleeve I865. The sleeve I 86 is also provided with a radial passage opening into a-longitudinally extending internal groove 206 disposed pposite the radial passages 2st and 2112 and having a length substantially equal to the axial spacing of these radial passages. A source-of fluid pressure is transmitted to the radial sleeve passage 204 through a conduit 208. The radial sleeve passage 2% is in communication with the an nular chamber I'IG via a passage 2I0 and a conduit 2I2 and the radial sleevepassage 202'is in communication with the annular chamber I34 via a passage Qitand a conduit-2H3.

Withthe valve plug I88 in the position illustrated in Figure 2, the longitudinal groove 2% straddles both radial passages 200 and 2 ilzwhereby both annular chambers E64 and I16 are connected to the drain passage I90 and both friction brakes are disengaged. Assuming counterclockwise rotation of the input shaft, as viewed in Figure 4, then the planet carrier I32; I34; .l36 will rotate counterclockwise and the internal gear I48 will also tend to rotate counterclockwise.

counterclockwise rotation of the internal gear I48 is prevented by one-way brake rollers 222 whereupon the transmission provides a low'stepup drive ratio from the intermediate shaft I24 to the output shaft I 44.

The one-way brake rollers 222 are disposed'in a cage 22 i and the internal gear I48 is splined Ito a cam member 226 having cam surfaces 228'. The rollers 2 22 are disposed between the cam surfaces 228 and a cylindrical drum 239 secured to the l i'ousing I28 by the bolts I42 whereby therollers '222 permit clockwise rotation of the internal gear Hi8 but preventcounterclockwiserotation of' this gear as viewed in Figure l.

' Whenthe valve plug Itl'is moved upwardly to its mid position, as indicated by the dotted'lines at2 I8; the annular-chamber "5 remains in communication with the drain passage I50 but the source of fluid pressure in conduit 208' is. now transmitted to the chamber I'M via annular groove I92, conduit 2I5and passage 2M. The friction plates I52 and I54 are thereby clamped together to lock the internal gear I45 against rotation whereupon the transmission provides an intermediate step-up drive ratio from the shaft IZ-d to the output shaft M l. The internal gear I48 and cam member 226 now rotate clockwise, as viewed in Figures 3'and4, so that-the "one way brake rollers 222'are ineffective orsdisengaged. The rollers 222-rotateclockwise with the cam member 226 Whereuponthe rollers are held radially outwardly in the pockets 23I at the end of their associated cam surfaces228 bythe centrifugal force acting entire-rollers. In this way, there is no contact ofjthe rollers with the stationary drum when the rollers: are disengaged;

If the valve plug I83 is shifted downibackzto its full line position, both friction brakesare again disengaged whereuponthe internal gear I48 and the cam member 226 decelerate. this deceleration, the inertia of the rollers 222 and their cage 22 l will'tend to cause thezrollers' to move clockwise ahead of the cam member 226 (as viewed in Figure 4) but the centrifugal forces acting on the. rollers will hold the rollers intheir pockets 23I out of contact with the drum 23. until the speed of the cam member. 226- reaches a; low value. When the speed of the cammemher 225', and therefore the centrifugal force acting on'the rollers, reaches-some 10w value,.theinertia. of 'therollers and their cage will be suflicientto cause them to move clockwise (as viewed in Figure 4-) relative to the cam member 226into' contact between the cam surfaces 228' and the 1 outer cylindrical surface on the drum 239. Thus, no springs or other means are needed to movethe rollers intoposition for engagement. Asasoon as thedirection of rotation of the cam member 22% tends to reverse, the rollers 222 engageto prevent such reverse rotation. Accordingly, the rollers 222 engage substantially without shock and there is no frictional drag on the rollers exceptfor asmall timeintervalprior. to their engagement.

When th valve plug I38 is moved to its extreme upper position, indicated, by the dottedlines at 22%, the chamber I64 is connected to thedrain passage Illil via passage I96, conduit'ZIB and passage 2 I l. At the same time, the chamber [TB is placed in communication with the fluid pressure. supply conduit 238 via the .annular groove I82, conduit'z I 2 and passage 2 I I3. As a result, the friction'plates I65 and I58 are clamped together thereby locking the planet carrier I32, I34, I36 against rotation. The transmission now provides a high step-up drive ratio from the'intermediate shaft I215 to the output shaft I44. In this speed ratio, as in the intermediate speed ratio, the internal gear I lil'rctates clockwise, as viewed in Figures 3 and 4, and thereforethe .one-' way brake rollers 222 are ineffective.

The constructions of Figures l and-'B areiquite similar. Thus, in Figure 1, a friction brake is provided for holding a planet carrier stationary at which time the double planet pinions provide a step-up drive ratio. In addition, in Figure 11a second friction brake is provided for holding stationary an internal gear meshing with the larger of the double planet pinion gears thereby'providing a second but smaller'step-up drive ratio. Figure 3 is similar except a one-way brake 222 has replaced this second friction brake. Qbviously, a one-way brake could be substituted in Figure l for the second friction brake comprising the plates I6 and I8. In addition, in Figure-3 a friction brake is provided for holding stationary an internal gear meshing with the smaller of the double planet pinion gears thereby providing an additional or intermediate step-up drive ratio.

Figures 5 to '7 illustrate a modification of Figure Bin which the intermediate speedratio-is provided by a one-way clutch instead of a friction brake. These modifications are otherwiseidentical and like parts are indicated by like reference numerals.

In Figuresfitc 7 instead of providing an internal. gear in mesh with the smaller planet pinions I28 together with a brake selectively engageable with the internal gear, a. one-way clutch comprising rollers 25% is provided between During the planet carrier portion I 34 and a cam member 252. The cam member 252 is splined to the rim of a plate 254 secured to the studs II3 by bolts H5. The rollers 250 are mounted in a cage 253 and are disposed between the outer cylindrical surface on the planet carrier portion I34 and the internal cam surfaces 251 on the cam member 252. Accordingly, the centrifugal force acting on the rollers 256 holds the rollers in their pockets 25I out of contact with the planet carrier portion I34.

The arrangement is such that when the friction brake plates I66 and I68 are released, the planet carrier I32, I34, I36 starts to rotatein the same direction as the input shaft III), namely counterclockwise as viewed in Figure 6, and the one-Way clutch rollers 256 restrain the planet carrier against rotation at a speed greater than that of the input shaft II6. Accordingly, when the friction brake plates I66 and I68 are disengaged, the one-way clutch rollers 256 provide a step-up drive ratio from the intermediate shaft I24 to the output shaft I44 which speed ratio is intermediate that provided by engagement of the friction brake plates I66 and I68 and that provided by engagement with one-way brake comprising the rollers 222.

With this construction, it is necessary that means be provided to render the one-way clutch rollers 256 inoperative to prevent rotation of the planet carrier I32, I34, I36 at a speed in excess of that of the input shaft I I6, otherwise the oneway brake 222 could never be rendered effective. To this end, the cage 256 for the rollers 256 is provided with a plurality of radially extending fingers 258. In addition, a plurality of plungers 266 are slidably disposed in the cam member 252. The plungers 266 are each provided with inclined surfaces 262 which are so disposed relative to the roller cage fingers 258 that upon axial movement of the plungers to the left in Figure 5, the inclined surfaces 262 effect counterclockwise rotation of the roller cage 256 (Figure 6) relative to the cam member 252, thereby moving the rollers into contact between the cam surfaces 251 and the cooperating outer surface of the planet carrier portion I34.

The outer end of each plunger 286 is secured to an annular plate 264 which is provided with a groove 266 about its periphery. A piston 266, slidably disposed relative to a fixed annular member 216, is provided with fingers 212 extending into the annular groove 266. The piston 268 is provided with seal rings 214 cooperating with the annular member 216 to provide a sealed chamber 216 corresponding to the sealed chamber I64 of Figure 2. A spring 218 serves to urge the pistons I12 and 268 away from each other as in Figure 2.

When the chamber I16 is relieved of fluid pressure and fluid pressure is supplied to the chamber 216, piston 268 and annular plate 264 are moved to the left, from their position illustrated in Figure 5, thereby pulling the plungers 266 to the left and moving the rollers 256 into contact between the cam surfaces 251 and the cooperat-ing cylindrical surface on the planet input shaft whereupon the one-way clutch rollers 256 engage to prevent the planet carrier from exceeding the speed of the input shaft and the double planet pinions I28, I36 provide a stepup drive ratio between the intermediate shaft I24 and the output shaft I44.

If the annular chamber 216 is now relieved of fluid pressure, the spring I62 acting against the piston 268 will return the plungers 266 to their retractive positions thereby freeing the roller cage fingers 258. Then, if fluid pressure is supplied to the chamber I16 to engage the brake plates I65 and I68, the planet carrier I32, I34, I36 will be held against-rotation whereupon the rotation of the cam member 252 will return the rollers 256 and their cage 256 to the position illustrated in Figure 5. The centrifugal force acting on the rollers 256 helps to return the rollers to their pockets 25I. At the same time, with said planet carrier held stationary, the double planet pinions 2| 8, I30 provide a step-up drive ratio from the intermediate shaft I24 to the output shaft I44, as in Figure 2, this latter ratio being larger than the step-up ratio provided when the one-way clutch rollers 256 are engaged. If the chamber I16 is now also relieved of fluid pressure, then both the friction brake and the one-way clutch rollers 256 will be disengaged and the one-way brake rollers 222 will engage to provide a step-up drive ratio between the intermediate shaft I24 and the output shaft I44 as in Figure 2, this latter ratio being smaller than either of the other two ratios.

In order to disengage the one-way clutch rollers 256, it is not only necesary to relieve the chamber 216 of fluid pressure in order to retract the plungers 266 but it is also necessary to engage the brake plates I66 and I68 to force the rollers 256 out from their wedged positions between the cam surfaces 251 and the cooperating cylindrical surface on the planet carrier portion I34. To this end, in Figure 5, the valve I84 is connected in such a manner that the chamber I16 is connected to the radial passage 262 instead of, as in Figure 2, to the radial passage 266 and the chamber 216 is connected to the radial passage 266.

With this connection of the valve I84, when the valve plug I88 is in its lowermost position, as illustrated in Figure 5, both annular chambers I16 and 216 are connected to the valve drain passage I86. Accordingly, the one-way brake rollers 222 engage to prevent counterclockwise rotation of the internal gear I48 thereby providing the transmission with its low step-up speed drive ratio.

When the valve plug I88 is raised to its mid position, indicated at 2I8, the annular chamber 216 remains in communication with the drain passage I96 but fluid pressure is now transmitted to the annular chamber I16 via annular groove I92, conduit 2I2 and passage 2I6. Accordingly, the friction plates I66 and I68 are clamped together thereby locking the planet carrier I32, I34, I36 against rotation. The transmission now provides a high step-up drive ratio from the shaft I24 to the shaft I44.

When the valve plug I88 is raised to its uppermost position, indicated at 226, the annular chamber I16 is connected to the drain passage I66 via passage I96, conduit 2I2 and passage 2I6 thereby disengaging the brake plates I56 and IE8 and freeing the planet carrier I32, I34, I36.

At the same time, fluid pressure is supplied to the chamber 216 via annular grooves I92, conduit 216 and passage 2M. Therefore, the piston 268 and plate 266 are moved to the left from their position illustrated in Figure .5 whereupon the inclined surfaces 262 ion the plungers 2'60 rotate therollercage 25dcounterclockwise, as viewed in Figure fi. Thus, the rollers 250- aremovedinto contact between the cam surfaces 25'! andthe outer cylindrical surface of the planet carrier portion I35. The planet carrier rotates in a counterclockwise direction and acceleratesuntil its speed-tends to exceed that of the input shaft whereupon the rollers 25!] engage to prevent anyiurther increase in speed of the planet carrierlrelative to themput shaft. The transmissionthen provides an intermediate step-up drive ratio from the shaft .l 2,4. to, the output shaft I'M, lpoth thisiintermediate speed ratio and in the high speed ratio of the transmision, the internal gear I48 rotates clockwise whereupon one-way brake rollers 222 are ineffective.

In order to shift back into the low speed ratio from the intermediate speed ratio of the transmission, it is first necessary to move the valve through its mid position whereupon the friction plates I56 and I68 are engaged to place the transmission in its high speed ratio thereby forcing the one-way clutch rollers 25!! out from their engaged positions to their inoperative positions as previously described. The centrifugal force acting on the rollers 25!] helps to move the rollers outwardly into the pockets 25! from their engaged positions.

While I have described my invention in detail in its present preferred embodiment, it will be obvious to those skilled in the art, after understanding my invention, that various changes and modifications may be made therein without departing from the spirit or scope thereof. I aim in the appended claims to cover all such modifications.

I claim as my invention:

1. In a transmission, an input shaft, an output shaft, a pair of concentric sun gears each drivably connected to one of said shafts, a plurality of pairs of planet pinions, the planet pinions of each pair being rotationally rigid relative to each other with one planet pinion of each pair disposed in meshing engagement with one of said sun gears and with the other planet pinion disposed in meshing engagement with the other of said sun gears, an internal gear concentrio with said sun gears and meshing with one of the planet pinions of each pair, a carrier for said plane-t pinions, a first brake engageable to hold said carrier stationary, a second brake automatically engageable to prevent rotation of said internal gear in one direction, and a clutch automatically engageable to prevent rotation of said carrier at a speed in excess of and in the same direction as that of said input shaft, the drive connection between said input shaft and its associated sun gear being such that the ratio of the speed of said sun gear to the speed or said input shaft is greater than unity.

2. In a transmission, an input shaft, an output shaft, a pair of concentric sun gears each drivably connected to one of said shafts, a plurality of pairs of planet pinions, the planet pinions of each pair being rotationally rigid relative to each other with one planet pinion of each pair disposed in meshing engagement with one of said sun gears and with the other planet pinion disposed in meshing engagement with the other of said sun gears, an internal gear 10 conce trio with said sun gears and meshing with sane ihel'e i n ni n a hp n-"a 3 riei ior said planet pinions, a pair of brakes, oneof said brakes being engageableto prevent rotation of said carrier in at least one direction and the other of said brakes being engageable to prevent rotation of ,said internal gear inat least one direction, and, a clutchengageable to prevent rotation er said carrier at speed-in excessof that of said input shaft, the .drive con,-

' nection between said input shaft and its associe .ated sun, gear-being such that the ratio. of the speed of said sun gear to the speed of said input it is greater than unity, said carrier having a ,rnulti-part" construction including first, sec; ,gndandthird annular parts rigidly secured to: ge'ther and having annular bearing engagement with said internal gear, said first and second annular carrier parts being disposed axially beyond opposite ends of said pairs of pinions to provide an annular bearing support for the two ends of said carrier and said third part/being disposed intermediate said first and second parts and extending between said sun gears so that one of said sun gears has annular bearing engagement externally about said third part and the other of said sun gears has annular internal bearing engagement with said third part.

3. In a transmission: a pair of co-axial sun gears; a plurality of pairs of planet pinions, the planet pinions of each pair being rotationally rigid relative to each other with one planet pinion of each pair being disposed in meshing engagement with one of said sun gears and with the other planet pinion of each pair being disposed in meshing engagement with the other of said sun gears; an internal gear co-axial with said sun gears and meshing with one of the planet pinions of each pair of said pinions; a carrier for said planet pinions; and a pair of brakes, one of said brakes being engageable to prevent rotation of said carrier in at least one direction and the other of said brakes being engageable to prevent rotation of said internal gear in at least one direction, said carrier havin a multi-part construction including first, second and third annular parts rigidly secured together and having annular bearing engagement with said internal gear, said first and sec- 0nd annular carrier parts being disposed axially beyond opposite ends of said pairs of pinions to provide an annular bearing support for the two ends of said carrier and said third carrier part being disposed intermediate said first and second parts and extending between said sun gears so that one of said sun gears has annular external bearin engagement with said third part and the other of said sun gears has annular intatrnal bearing engagement with said third par 4. In a transmission, an input shaft, an output shaft, a pair of co-axial sun gears each drivably connected to one of said shafts, a plurality of pairs of planet pinions, the planet pinions of each pair being rotationally rigid relative to each other with one planet pinion of each pair disposed in meshing engagement with one of said sun gears and with the other planet pinion disposed in meshing engagement with the other of said sun gears, a pair of internal gears co-axial with said sun gears and each meshing with one of the planet pinions of each pair, a carrier for said planet pinions, a first brake engageable to prevent rotation of said carrier, a second brake engageable to prevent rotation of one of said internal gears, and a third brake engageable to prevent rotation of the other of said internal gears, said carrier having a multi-part construction including first, second and third annular parts rigidly secured together and having annular bearing engagement with said internal gears, said first and second annular carrier parts being disposed axially beyond opposite ends of said pairs of pinions to provide an annular bearing support for the two ends of said carrier and said third carrier part being disposed intermediate said first and second parts and extending between said sun gears so that one of said sun gears has annular external bearing engagement with said third part and the other of said sun gears has annular internal bearing engagement with said third part.

STANLEY W. BAKER.

REFERENCES CITED The following references are of record in the file of this patent:

Number Number UNITED STATES PATENTS Name Date Salter May 26, 1908 Silvius Nov. 30, 1920 Saki July 14, 1931 Saki July 14, 1931 Browne Apr. 28, 1936 Booth Aug. 4, 1936 Cutler Nov. 23, 1937 Towns et al Dec. 13, 1938 Hunter Nov. 12, 1940 Hale Aug. 5, 1941 Tipton Sept. 24, 1946 FOREIGN PATENTS Country Date France Jan. 17, 1903 

